In recent years, vehicles such as a hybrid car and an electric car, which use a motor for driving, have been developed increasingly. However, when a motor is used for driving, further downsizing and high power of a motor are demanded. Main conventional motors use coils each formed by winding a wire having a circular cross section. In response to demands for downsizing and high power to be used as driving of vehicles, the use of a coil formed of a rectangular wire having a rectangular cross section in a motor has been studied. This results in an advantage that the use of the rectangular wire is effective in enhancing a lamination factor of a stator and increasing high power.
Patent Document 1 discloses a technique of an edgewise coil winding method and a winding device. While a bent portion of a rectangular wire fed each by a preset length is held by a supporting member of a main clamp serving as a bending means and a bender, and a side of the continuous rectangular wire to be supplied is fixed to the bending means, the bender is rotated about the supporting member to bend the held rectangular wire, thus forming the edgewise coil. At that time, a coil guide is engaged with an inner circumference side of the edgewise coil to be formed, and the coil guide is moved to follow the movement of the edgewise coil by a feeding operation of the rectangular wire. Thus, the coil guide is rotated and moved according to the bending operation to follow the movement of the edgewise coil. In the above way, it is possible to suppress wobble and swing of a coil caused during coil winding.